Currently, field-effect transistors are almost formed of semiconductor materials with single element, compound elements or organic compound elements. Other than those elements described above, biomaterials have been widely employed in field-effect transistors.
In one example, β-carotene has been reported as an active layer for a field-effect transistor. See Synth. Met. 2004, 146, 43. In another example, deoxyribonucleic acid-hexadecyltrimethylammonium chloride (DNA-CTMA) has been reported and used as a dielectric layer for a field-effect transistor. See J. Appl. Phys. 2006, 100, 024514, Appl. Phys. Lett. 2009, 95, 263304, and Appl. Phys. Lett. 2010, 96, 103307. In still another example, nucleobase has also been reported and used as a dielectric layer for a field-effect transistor. See Org. Electron. 2010, 11, 1974. In still another example, silk has been used as a dielectric layer or a substrate for a field-effect transistor. See Adv. Mater. 2011, 23, 1630 and Nat. Mater 2010, 9, 511. In still another example, poly(L-lactide-co-glycolide) (PLGA) has also been used as a substrate for a field-effect transistor. See Adv. Mater 2010, 22, 651.
Biomaterials are essentially biodegradable, bio-absorbable, biocompatible, environment-friendly, and no chemical synthesization required. Biomaterials are easily acquired so that process of manufacturing the field-effect transistor is simplified and the production is inexpensive. Therefore, it is desirable to exploit more biomaterials in the field-effect transistor so as to reduce cost in the production of the field-effect transistor and to exhibit electric behavior equivalent to or better than that of any prior field-effect transistor.